1/* A correct <float.h>. 2 3 Copyright (C) 2007-2022 Free Software Foundation, Inc. 4 5 This file is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as 7 published by the Free Software Foundation; either version 2.1 of the 8 License, or (at your option) any later version. 9 10 This file is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18#ifndef _@GUARD_PREFIX@_FLOAT_H 19 20#if __GNUC__ >= 3 21@PRAGMA_SYSTEM_HEADER@ 22#endif 23@PRAGMA_COLUMNS@ 24 25/* The include_next requires a split double-inclusion guard. */ 26#@INCLUDE_NEXT@ @NEXT_FLOAT_H@ 27 28#ifndef _@GUARD_PREFIX@_FLOAT_H 29#define _@GUARD_PREFIX@_FLOAT_H 30 31/* 'long double' properties. */ 32 33#if defined __i386__ && (defined __BEOS__ || defined __OpenBSD__) 34/* Number of mantissa units, in base FLT_RADIX. */ 35# undef LDBL_MANT_DIG 36# define LDBL_MANT_DIG 64 37/* Number of decimal digits that is sufficient for representing a number. */ 38# undef LDBL_DIG 39# define LDBL_DIG 18 40/* x-1 where x is the smallest representable number > 1. */ 41# undef LDBL_EPSILON 42# define LDBL_EPSILON 1.0842021724855044340E-19L 43/* Minimum e such that FLT_RADIX^(e-1) is a normalized number. */ 44# undef LDBL_MIN_EXP 45# define LDBL_MIN_EXP (-16381) 46/* Maximum e such that FLT_RADIX^(e-1) is a representable finite number. */ 47# undef LDBL_MAX_EXP 48# define LDBL_MAX_EXP 16384 49/* Minimum positive normalized number. */ 50# undef LDBL_MIN 51# define LDBL_MIN 3.3621031431120935063E-4932L 52/* Maximum representable finite number. */ 53# undef LDBL_MAX 54# define LDBL_MAX 1.1897314953572317650E+4932L 55/* Minimum e such that 10^e is in the range of normalized numbers. */ 56# undef LDBL_MIN_10_EXP 57# define LDBL_MIN_10_EXP (-4931) 58/* Maximum e such that 10^e is in the range of representable finite numbers. */ 59# undef LDBL_MAX_10_EXP 60# define LDBL_MAX_10_EXP 4932 61#endif 62 63/* On FreeBSD/x86 6.4, the 'long double' type really has only 53 bits of 64 precision in the compiler but 64 bits of precision at runtime. See 65 <https://lists.gnu.org/r/bug-gnulib/2008-07/msg00063.html>. */ 66#if defined __i386__ && (defined __FreeBSD__ || defined __DragonFly__) 67/* Number of mantissa units, in base FLT_RADIX. */ 68# undef LDBL_MANT_DIG 69# define LDBL_MANT_DIG 64 70/* Number of decimal digits that is sufficient for representing a number. */ 71# undef LDBL_DIG 72# define LDBL_DIG 18 73/* x-1 where x is the smallest representable number > 1. */ 74# undef LDBL_EPSILON 75# define LDBL_EPSILON 1.084202172485504434007452800869941711426e-19L /* 2^-63 */ 76/* Minimum e such that FLT_RADIX^(e-1) is a normalized number. */ 77# undef LDBL_MIN_EXP 78# define LDBL_MIN_EXP (-16381) 79/* Maximum e such that FLT_RADIX^(e-1) is a representable finite number. */ 80# undef LDBL_MAX_EXP 81# define LDBL_MAX_EXP 16384 82/* Minimum positive normalized number. */ 83# undef LDBL_MIN 84# define LDBL_MIN 3.362103143112093506262677817321752E-4932L /* = 0x1p-16382L */ 85/* Maximum representable finite number. */ 86# undef LDBL_MAX 87/* LDBL_MAX is represented as { 0xFFFFFFFF, 0xFFFFFFFF, 32766 }. 88 But the largest literal that GCC allows us to write is 89 0x0.fffffffffffff8p16384L = { 0xFFFFF800, 0xFFFFFFFF, 32766 }. 90 So, define it like this through a reference to an external variable 91 92 const unsigned int LDBL_MAX[3] = { 0xFFFFFFFF, 0xFFFFFFFF, 32766 }; 93 extern const long double LDBL_MAX; 94 95 Unfortunately, this is not a constant expression. */ 96# if !GNULIB_defined_long_double_union 97union gl_long_double_union 98 { 99 struct { unsigned int lo; unsigned int hi; unsigned int exponent; } xd; 100 long double ld; 101 }; 102# define GNULIB_defined_long_double_union 1 103# endif 104extern const union gl_long_double_union gl_LDBL_MAX; 105# define LDBL_MAX (gl_LDBL_MAX.ld) 106/* Minimum e such that 10^e is in the range of normalized numbers. */ 107# undef LDBL_MIN_10_EXP 108# define LDBL_MIN_10_EXP (-4931) 109/* Maximum e such that 10^e is in the range of representable finite numbers. */ 110# undef LDBL_MAX_10_EXP 111# define LDBL_MAX_10_EXP 4932 112#endif 113 114/* On AIX 7.1 with gcc 4.2, the values of LDBL_MIN_EXP, LDBL_MIN, LDBL_MAX are 115 wrong. 116 On Linux/PowerPC with gcc 4.4, the value of LDBL_MAX is wrong. */ 117#if (defined _ARCH_PPC || defined _POWER) && defined _AIX && (LDBL_MANT_DIG == 106) && defined __GNUC__ 118# undef LDBL_MIN_EXP 119# define LDBL_MIN_EXP DBL_MIN_EXP 120# undef LDBL_MIN_10_EXP 121# define LDBL_MIN_10_EXP DBL_MIN_10_EXP 122# undef LDBL_MIN 123# define LDBL_MIN 2.22507385850720138309023271733240406422e-308L /* DBL_MIN = 2^-1022 */ 124#endif 125#if (defined _ARCH_PPC || defined _POWER) && (defined _AIX || defined __linux__) && (LDBL_MANT_DIG == 106) && defined __GNUC__ 126# undef LDBL_MAX 127/* LDBL_MAX is represented as { 0x7FEFFFFF, 0xFFFFFFFF, 0x7C8FFFFF, 0xFFFFFFFF }. 128 It is not easy to define: 129 #define LDBL_MAX 1.79769313486231580793728971405302307166e308L 130 is too small, whereas 131 #define LDBL_MAX 1.79769313486231580793728971405302307167e308L 132 is too large. Apparently a bug in GCC decimal-to-binary conversion. 133 Also, I can't get values larger than 134 #define LDBL63 ((long double) (1ULL << 63)) 135 #define LDBL882 (LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63) 136 #define LDBL945 (LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63) 137 #define LDBL1008 (LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63 * LDBL63) 138 #define LDBL_MAX (LDBL1008 * 65535.0L + LDBL945 * (long double) 9223372036821221375ULL + LDBL882 * (long double) 4611686018427387904ULL) 139 which is represented as { 0x7FEFFFFF, 0xFFFFFFFF, 0x7C8FFFFF, 0xF8000000 }. 140 So, define it like this through a reference to an external variable 141 142 const double LDBL_MAX[2] = { DBL_MAX, DBL_MAX / (double)134217728UL / (double)134217728UL }; 143 extern const long double LDBL_MAX; 144 145 or through a pointer cast 146 147 #define LDBL_MAX \ 148 (*(const long double *) (double[]) { DBL_MAX, DBL_MAX / (double)134217728UL / (double)134217728UL }) 149 150 Unfortunately, this is not a constant expression, and the latter expression 151 does not work well when GCC is optimizing.. */ 152# if !GNULIB_defined_long_double_union 153union gl_long_double_union 154 { 155 struct { double hi; double lo; } dd; 156 long double ld; 157 }; 158# define GNULIB_defined_long_double_union 1 159# endif 160extern const union gl_long_double_union gl_LDBL_MAX; 161# define LDBL_MAX (gl_LDBL_MAX.ld) 162#endif 163 164/* On IRIX 6.5, with cc, the value of LDBL_MANT_DIG is wrong. 165 On IRIX 6.5, with gcc 4.2, the values of LDBL_MIN_EXP, LDBL_MIN, LDBL_EPSILON 166 are wrong. */ 167#if defined __sgi && (LDBL_MANT_DIG >= 106) 168# undef LDBL_MANT_DIG 169# define LDBL_MANT_DIG 106 170# if defined __GNUC__ 171# undef LDBL_MIN_EXP 172# define LDBL_MIN_EXP DBL_MIN_EXP 173# undef LDBL_MIN_10_EXP 174# define LDBL_MIN_10_EXP DBL_MIN_10_EXP 175# undef LDBL_MIN 176# define LDBL_MIN 2.22507385850720138309023271733240406422e-308L /* DBL_MIN = 2^-1022 */ 177# undef LDBL_EPSILON 178# define LDBL_EPSILON 2.46519032881566189191165176650870696773e-32L /* 2^-105 */ 179# endif 180#endif 181 182#if @REPLACE_ITOLD@ 183/* Pull in a function that fixes the 'int' to 'long double' conversion 184 of glibc 2.7. */ 185extern 186# ifdef __cplusplus 187"C" 188# endif 189void _Qp_itoq (long double *, int); 190static void (*_gl_float_fix_itold) (long double *, int) = _Qp_itoq; 191#endif 192 193#endif /* _@GUARD_PREFIX@_FLOAT_H */ 194#endif /* _@GUARD_PREFIX@_FLOAT_H */ 195